A feather found in a finch nest is all the proof scientists need to prove the elusive night parrot exists around Lake Eyre in South Australia — an area where the ground-dwelling bird has not been seen in 170 years.

The parrot is nocturnal and extremely elusive, meaning researchers across Australia struggle to map its whereabouts.

Some of the first night parrot specimens were taken from northern South Australia in 1845, but since then there has been no hard proof the bird still lived there.

However in July this year, ecologists John Young and Keith Bellchambers from the Australian Wildlife Conservancy (AWC), found a feather from the parrot on Kalamurina Station, around northern Lake Eyre.

"The significance of what we just found is way beyond what I could have imagined," Mr Young said.

"When I did come across the feather it was a mind-blowing experience, I started shaking uncontrollably."

The AWC sent the feather to the Western Australian Museum for confirmation it was that of a night parrot.

Gregory Andrews, Australia's Threatened Species Commissioner, said the discovery would excite bird enthusiasts, but cautioned them against visiting the area to see for themselves.

"Australians love their wildlife and bird watchers from time to time can have a reputation for being quirky and interested to find birds, but AWC will do its best to protect this population," he said.

Given detections of the night parrot are becoming more common, and new habitats are being discovered, Mr Andrews cautioned against an illegal bird trade emerging.

"Australia has some of the strictest illegal wildlife trade laws in the world," he said.

"I can assure you that the Federal Environment Minister, Josh Frydenburg, and myself will be ensuring that anybody who does anything unlawful or inhibits this bird will face the full strength of the law."